7. Gastrointestinal system Flashcards
What do Chief cells do?
They secrete pepsinogen and lipase precursor.
What do Parietal cells?
They secrete HCl and intrinsic factor.
What Enteroendocrine (EE) cells do?
They secrete a variety of peptide hormones.
What do Brunner cells do?
They secrete an alkaline secretion.
What do Paneth cells do?
They contain granules that contain lysozyme. May play a role in regulating intestinal bacterial flora. They are found in the bases of the crypts of Lieberkuhn.
What do Goblet cells do?
They secrete acid glycoproteins that protect mucosal lining.
Which cranial nerve innervates the parotid gland?
Glossopharyngeal (IX)
Which cranial nerve innervates the submandibular and sublingual gland?
Facial (VII)
What do acini cells do?
They are par of the exocrine part of the pancreas and they secrete enzymes that secrete proteins, carbohydrates and nucleic acids.
What do duct cells do?
They are part of the exocrine part of the pancreas and they secrete water, electrolytes, and bicarbonate (HCO3-) which dilute enzymes secretions and neutralize acidic chyme.
What is the Space of Disse?
AKA perisinusoidal space, it is a location in the liver between a hepatocyte and a sinusoid. It contains the blood plasma. Microvilli of hepatocytes extend into this space, allowing proteins and other plasma components from the sinusoids to be absorbed by the hepatocytes. Fenestration and discontinuity of the endothelium, as well as its basement membrane, facilitates this transport. This space may be obliterated in liver disease, leading to decreased uptake by hepatocytes of nutrients and wastes (e.g., bilirubin). This space also contains Ito cells, also called hepatic stellate cells, which store fat or fat soluble vitamins (like vitamin A). A variety of insults that cause inflammation can result in Ito cells transforming to myofibroblasts, resulting in collagen production, fibrosis, and cirrhosis.
What are Kupffer cells?
They are hepatic cells that line the liver sinusoids that phagocyte red blood cells and particles and contain cytoplasmic residual bodies of iron and pigments.
What are Hering canals?
AKA intrahepatic bile ductules, they are part of the outflow system of exocrine bile product from the liver.
How does the gallbladder concentrate bile?
By actively transporting Na, Cl, and water from the cytoplasm to the intercellular space. From there, the water moves into the blood vessels, and the bile is concentrated.
Which hormone influences the contraction of the gallbladder muscle?
Contraction of the muscle layer (muscularis externa) of the gallbladder is induced by the hormone cholecystokinin.
